Pancreas Divisum and “Santorinicele”: Diagnosis with Dynamic MR Cholangiopancreatography with Secretin Stimulation

PURPOSE: To evaluate the usefulness of magnetic resonance (MR) cholangiopancreatography (MRCP) before and after secretin administration in diagnosing santorinicele in patients with pancreas divisum. MATERIALS AND METHODS: One hundred seven patients suspected of having pancreatic disease underwent MRCP before and after secretin administration (S-MRCP). S-MRCP images were evaluated for pancreas divisum and santorinicele and for size of the main pancreatic duct and santorinicele. The onset of duodenal filling was calculated on dynamic S-MRCP images. RESULTS: Pancreas divisum was detected in five (5%) of 107 patients at MRCP and in 10 (9%) of 107 patients at S-MRCP. Santorinicele was detected in three (21%) of 14 patients at MRCP and in an additional four (seven [50%] of 14) patients at S-MRCP in patients with pancreas divisum. Santorinicele was confirmed in six of seven patients at endoscopic retrograde cholangiopancreatography (ERCP); in one of seven patients, ERCP was unsuccessful. The duct of Santorini was significantly (P: <.05) larger in the pancreatic head in patients with pancreas divisum and santorinicele (3.6 mm) compared with those with only pancreas divisum (2.2 mm). A noteworthy reduction in size of the pancreatic duct (26%) and of the santorinicele (63%) was observed after sphincterotomy. The onset of duodenal filling was delayed significantly in patients with santorinicele (2.1 vs 1.3 minutes; P: <.05). CONCLUSION: S-MRCP helps in identifying pancreas divisum and santorinicele, which may be the cause of impeded pancreatic outflow.